Category Archives: sexual selection

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And all of those are found in just one species, the Pieris rapae, the cabbage white butterfly.

In an wonderful piece over at the Atlantic, we learn about the crazy sex life/organs of this very common butterfly.

I was enthralled reading the whole thing, but the main investigator is quoted below, is really why I’m sharing this.

“Jumping spiders with telescope eyes are singing and dancing to impress their mates. That butterfly on your kale has a chewing jaw in its reproductive tract that helps it to regain control over its own reproductive timing. It is this ability of life to continually surprise us that brings me such joy as a scientist. And it’s my hope that, in some small way, my work can return some childlike wonder to the daily lives of others. It is only through falling back in love with nature that we stand any chance of saving it.” –Nathan Morehouse

Genitals are weirdly shaped, which is strange. They only really NEED to be a pipette like device to inject sperm into a cup like device. But what we see in nature is way more complicated and bizarre. The reason? “They’re the result of a furious evolutionary tango of sex, that has been going on of millions of years.” Check out this cool video from TED-Ed to marvel at how odd genitalia are:

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Last spring, the journal Current Biology published a report describing something new under the entomological sun: A genus of tiny cave-dwelling insects, dubbed Neotrogla, in which females, not males, have penises.

Or, rather, the females have a thing that they stick inside the males. Once it’s in there, that thing inflates and latches into the male with tiny barbs, binding the couple together in a copulation lasting two to three days, while the thing collects a packet containing sperm and a whole lot of (potentially) nutritious protein. What to call the females’ thing seems to have puzzled even the scientists who described it. In the text of their paper, they call it a gynosome (literally, a “female body”); but in the title, it’s a “female penis.”

This synonymy went from confusing to controversial the moment it hit the popular science press, which almost uniformly chose to go penis-first. “Female insect uses spiky penis to take charge” read the headline in the prestigious journal Nature. “Meet the female insect with giant PENIS whose steamy sex sessions last 70 HOURS,” said the Daily Mirror, caps-locked emphasis sic. Most of the stories, even the Mirror’s, got around to using the word “gynosome” eventually, and many went into more detail about how the organ in question wasn’t really a penis as we know it. LiveSciencenoted it was “a complex organ composed of muscles, ducts, membranes and spikes,” before adding that its size, relative to the body of a Neotrogla female, was “the equivalent of a man who is 5 feet 9 inches (1.75 meters) tall having a penis about 9.8 inches (24.9 centimeters) long.”

Thanks to a remarkably good fossil record, it’s now well established whales and dolphins evolved from land mammals, their forelimbs adapting into flippers, and their hind-limbs almost entirely disappearing. If you’d asked me yesterday what’s going on with that almost—the last vestiges of the hip bones that whales retain, which have no legs to support or direct contact with the rest of their skeletons—I’d have told you they were evolutionary leftovers, and probably going to disappear in another million years or so. I think a lot of other evolutionary biologists (those who aren’t whale specialists, anyway) would’ve agreed with me. But it turns out we’d have been wrong.

As Carl Zimmer describes, a paper recently published in the journal Evolution points out that whales’ hips do have one remaining function, an important one—they anchor muscles that control the penis. And that function is under ongoing sexual selection.

The more promiscuous a [whale] species was, the bigger its pelvis bones tended to be. The scientists also found that as whales evolved to become more promiscuous, their pelvic bones changed shape. These changes weren’t part of some general change to their skeleton, however. The ribs near the hips didn’t show the same patterns of size and shape change.

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Basic science = scientific questions that are founded in understanding theory, or the natural world around us

Applied science = scientific research that is directly applicable to humans. i.e. Cancer research

The last few years of financial crisis have seen a rise in criticism over basic scientific research. NPR does a great job of summarizing the criticisms and explaining why seeking to understand duck genitalia is a solid biological question.

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Welcome, readers, to the 57th Carnival of Evolution. This past month, the 204th birthday of Charles Darwin just happened to fall on Mardi Gras, a celebration of life’s exuberant excesses. So put on your most dazzling mask, and join us for an exploration of the endless forms most beautiful to be found in the living, evolving world.

Evolutionary science

In addition to Darwin Day and Mardi Gras, February is the month of Valentine’s Day. So it’s maybe appropriate that evolutionary bloggers had sex on the brain. Joachim describes new research on the specific forms of natural selection that might have supported the evolution of sexual reproduction. Right here at Nothing in Biology Makes Sense!, Amy Dapper writes about one consequence of sex, among grass gobies: “sneaker” males with specialized sperm. And Jeremy Yoder (yours truly) takes a look at daisies that attract pollinators by fooling them into mating with deceptive flower petals.

While most songbird species breed before they even turn a year old, sociable weavers rarely breed before the age of two. Instead, these younger birds help raise other nestlings–their siblings as well as unrelated chicks–by gathering food and maintaining the nest’s fluffy interior chambers and external sticks and grass.